This invention relates generally to monitoring systems and more particularly concerns devices used to monitor bed patients in hospital or other care giving environments.
Known bed patient monitors using sensing mats to detect the presence of a patient suffer from a variety of drawbacks.
For one, known bed monitoring systems include externally accessible switches allowing the care giver to reconfigure the monitor circuits such as those circuits which establish the time lapse that must occur between the operation of the sensing mat and the giving of an alarm or the duration of the alarm. External switching makes tampering with the system extremely easy.
A further problem with known bed monitoring systems is that they use oscillating transducers in their audio circuits, resulting in single frequency audio alarms. Since bed monitor alarms are frequently employed in environments in which a multiplicity of other problems also result in audio alarms, if the single alarm sound provided by the bed monitor is similar to one or more other alarm sounds heard in response to different monitors, confusion and consequential inadequate response times to alarms may result.
Another problem with presently known bed monitoring systems is that, while it is frequently desirable to connect the system to a nurse call station, nurse call station configurations differ. It is, therefore, necessary to make internal modifications to the monitor if the nurse call station is not configured in the manner anticipated by the device.
Another failure in known bed monitoring systems is that they do not provide a method of logging statistical data with respect to the operation of the unit and the response times of the care giver to alarm conditions, information that could be very helpful to the maintenance and proper operation of the monitor.
It is, therefore, a primary object of this invention to provide a bed patient monitor that is microprocessor based so as to be reconfigurable by the uploading of configuration data to an electronically erasable programmable read only memory external to the microprocessor. A further object of this invention is to provide a microprocessor based bed patient monitor which synthesizes multiple alarm sounds in software for selection by the care giver. It is also an object of this invention to provide a microprocessor based bed patient monitor having a nurse call interface allowing interconnection with any nurse call station without modification of the monitor. Yet another object of this invention is to provide a microprocessor based bed patient monitor having an electrically erasable programmable read only memory external to the microprocessor for logging statistical data with respect to the use of the monitor and the response time of the care giver using the monitor. Another object of this invention is to provide a microprocessor based bed patient monitor which permits the downloading of the logged statistical data to a host microprocessor connected to the system.